Table 1 Demographic characteristics of participants.

From: Associations between essential trace elements and sleep quality in Iranian adults based on the Pittsburgh Sleep Quality Index

Demographic characteristics

Mean ± SD*or n. (%)

Age (year)

46.04 ± 12.75

BMI (kg/m2)

28.77 ± 5.81

Tea consumption (n)**

4.11 ± 3.07

Gender

 Female

42(42.4)

 Male

57(57.6)

Marital status

 Single

16(16.2)

 Married

83(83.8)

Level of education

 Illiterate

7(7.1)

 Primary

26(26.3)

 High school and diploma

25(25.3)

 Academic

41(41.4)

Smoking

 No

82(82.8)

 Yes

17(17.2)

Opioid

 No

88(88.9)

 Yes

11(11.1)

Underlying disease

 No

47(47.5)

 Yes

52(52.5)

Coffee consumption

 No

90 (90.9)

 Yes

9 (9.10)

  1. *Data are presented as n (%) for qualitative features, mean ± SD for quantitative features; **Number of times consumed per day.